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Cimmino L, Duarte AG, Ni D, Ekundayo BE, Pereira IAC, Stahlberg H, Holliger C, Maillard J. Structure of a membrane-bound menaquinol:organohalide oxidoreductase. Nat Commun 2023; 14:7038. [PMID: 37923808 PMCID: PMC10624902 DOI: 10.1038/s41467-023-42927-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2023] [Accepted: 10/26/2023] [Indexed: 11/06/2023] Open
Abstract
Organohalide-respiring bacteria are key organisms for the bioremediation of soils and aquifers contaminated with halogenated organic compounds. The major players in this process are respiratory reductive dehalogenases, corrinoid enzymes that use organohalides as substrates and contribute to energy conservation. Here, we present the structure of a menaquinol:organohalide oxidoreductase obtained by cryo-EM. The membrane-bound protein was isolated from Desulfitobacterium hafniense strain TCE1 as a PceA2B2 complex catalysing the dechlorination of tetrachloroethene. Two catalytic PceA subunits are anchored to the membrane by two small integral membrane PceB subunits. The structure reveals two menaquinone molecules bound at the interface of the two different subunits, which are the starting point of a chain of redox cofactors for electron transfer to the active site. In this work, the structure elucidates how energy is conserved during organohalide respiration in menaquinone-dependent organohalide-respiring bacteria.
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Affiliation(s)
- Lorenzo Cimmino
- Laboratory for Environmental Biotechnology, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Américo G Duarte
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade NOVA de Lisboa, Oeiras, Portugal
| | - Dongchun Ni
- Laboratory of Biological Electron Microscopy, Ecole Polytechnique Fédérale de Lausanne (EPFL), and Department of Fundamental Microbiology, University of Lausanne, Lausanne, Switzerland
| | - Babatunde E Ekundayo
- Laboratory of Biological Electron Microscopy, Ecole Polytechnique Fédérale de Lausanne (EPFL), and Department of Fundamental Microbiology, University of Lausanne, Lausanne, Switzerland
| | - Inês A C Pereira
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade NOVA de Lisboa, Oeiras, Portugal
| | - Henning Stahlberg
- Laboratory of Biological Electron Microscopy, Ecole Polytechnique Fédérale de Lausanne (EPFL), and Department of Fundamental Microbiology, University of Lausanne, Lausanne, Switzerland.
| | - Christof Holliger
- Laboratory for Environmental Biotechnology, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland.
| | - Julien Maillard
- Laboratory for Environmental Biotechnology, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland.
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2
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Madjarov J, Soares R, Paquete CM, Louro RO. Sporomusa ovata as Catalyst for Bioelectrochemical Carbon Dioxide Reduction: A Review Across Disciplines From Microbiology to Process Engineering. Front Microbiol 2022; 13:913311. [PMID: 35801113 PMCID: PMC9253864 DOI: 10.3389/fmicb.2022.913311] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Accepted: 05/23/2022] [Indexed: 11/13/2022] Open
Abstract
Sporomusa ovata is a bacterium that can accept electrons from cathodes to drive microbial electrosynthesis (MES) of acetate from carbon dioxide. It is the biocatalyst with the highest acetate production rate described. Here we review the research on S. ovata across different disciplines, including microbiology, biochemistry, engineering, and materials science, to summarize and assess the state-of-the-art. The improvement of the biocatalytic capacity of S. ovata in the last 10 years, using different optimization strategies is described and discussed. In addition, we propose possible electron uptake routes derived from genetic and experimental data described in the literature and point out the possibilities to understand and improve the performance of S. ovata through genetic engineering. Finally, we identify current knowledge gaps guiding further research efforts to explore this promising organism for the MES field.
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Affiliation(s)
- Joana Madjarov
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
| | - Ricardo Soares
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
- Instituto Nacional de Investigação Agrária e Veterinária, Oeiras, Portugal
| | - Catarina M. Paquete
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
| | - Ricardo O. Louro
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
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3
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Duarte AG, Barbosa ACC, Ferreira D, Manteigas G, Domingos RM, Pereira IAC. Redox loops in anaerobic respiration - The role of the widespread NrfD protein family and associated dimeric redox module. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2021; 1862:148416. [PMID: 33753023 DOI: 10.1016/j.bbabio.2021.148416] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 11/15/2020] [Revised: 02/25/2021] [Accepted: 03/11/2021] [Indexed: 02/06/2023]
Abstract
In prokaryotes, the proton or sodium motive force required for ATP synthesis is produced by respiratory complexes that present an ion-pumping mechanism or are involved in redox loops performed by membrane proteins that usually have substrate and quinone-binding sites on opposite sides of the membrane. Some respiratory complexes include a dimeric redox module composed of a quinone-interacting membrane protein of the NrfD family and an iron‑sulfur protein of the NrfC family. The QrcABCD complex of sulfate reducers, which includes the QrcCD module homologous to NrfCD, was recently shown to perform electrogenic quinone reduction providing the first conclusive evidence for energy conservation among this family. Similar redox modules are present in multiple respiratory complexes, which can be associated with electroneutral, energy-driven or electrogenic reactions. This work discusses the presence of the NrfCD/PsrBC dimeric redox module in different bioenergetics contexts and its role in prokaryotic energy conservation mechanisms.
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Affiliation(s)
- Américo G Duarte
- Instituto de Tecnologia Química e Biológica António Xavier/Universidade Nova de Lisboa, Av. da República, Estação Agronómica Nacional, 2780-157 Oeiras, Portugal.
| | - Ana C C Barbosa
- Instituto de Tecnologia Química e Biológica António Xavier/Universidade Nova de Lisboa, Av. da República, Estação Agronómica Nacional, 2780-157 Oeiras, Portugal
| | - Delfim Ferreira
- Instituto de Tecnologia Química e Biológica António Xavier/Universidade Nova de Lisboa, Av. da República, Estação Agronómica Nacional, 2780-157 Oeiras, Portugal
| | - Gonçalo Manteigas
- Instituto de Tecnologia Química e Biológica António Xavier/Universidade Nova de Lisboa, Av. da República, Estação Agronómica Nacional, 2780-157 Oeiras, Portugal
| | - Renato M Domingos
- Instituto de Tecnologia Química e Biológica António Xavier/Universidade Nova de Lisboa, Av. da República, Estação Agronómica Nacional, 2780-157 Oeiras, Portugal
| | - Inês A C Pereira
- Instituto de Tecnologia Química e Biológica António Xavier/Universidade Nova de Lisboa, Av. da República, Estação Agronómica Nacional, 2780-157 Oeiras, Portugal.
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4
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Kaiser J, Castellano M, Gnandt D, Koslowski T. Monte Carlo simulation and thermodynamic integration applied to protein charge transfer. J Comput Chem 2020; 41:1105-1115. [PMID: 31981372 DOI: 10.1002/jcc.26155] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Revised: 12/29/2019] [Accepted: 01/02/2020] [Indexed: 11/09/2022]
Abstract
We introduce a combination of Monte Carlo simulation and thermodynamic integration methods to address a model problem in free energy computations, electron transfer in proteins. The feasibility of this approach is tested using the ferredoxin protein from Clostridium acidurici. The results are compared to numerical solutions of the Poisson-Boltzmann equation and data from recent molecular dynamics simulations on charge transfer in a protein complex, the NrfHA nitrite reductase of Desulfovibrio vulgaris. Despite the conceptual and computational simplicity of the Monte Carlo approach, the data agree well with those obtained by other methods. A link to experiments is established via the cytochrome subunit of the bacterial photosynthetic reaction center of Rhodopseudomonas viridis.
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Affiliation(s)
- Jan Kaiser
- Institut für Physikalische Chemie, Universität Freiburg, Freiburg im Breisgau, Germany
| | - Mike Castellano
- Institut für Physikalische Chemie, Universität Freiburg, Freiburg im Breisgau, Germany
| | - David Gnandt
- Institut für Physikalische Chemie, Universität Freiburg, Freiburg im Breisgau, Germany
| | - Thorsten Koslowski
- Institut für Physikalische Chemie, Universität Freiburg, Freiburg im Breisgau, Germany
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5
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Gnandt D, Koslowski T. Long-range electron-electron interaction and charge transfer in protein complexes: a numerical approach. Phys Chem Chem Phys 2019; 21:18595-18604. [PMID: 31414082 DOI: 10.1039/c9cp03141c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
With application to the nitrite reductase hexameric protein complex of Desulfovibrio vulgaris, NrfH2A4, we suggest a strategy to compute the energy landscape of electron transfer in large systems of biochemical interest. For small complexes, the energy of all electronic configurations can be scanned completely on the level of a numerical solution of the Poisson-Boltzmann equation. In contrast, larger systems have to be treated using a pair approximation, which is verified here. Effective Coulomb interactions between neighbouring sites of excess electron localization may become as large as 200 meV, and they depend in a nontrivial manner on the intersite distance. We discuss the implications of strong Coulomb interactions on the thermodynamics and kinetics of charging and decharging a protein complex. Finally, we turn to the effect of embedding the system into a biomembrane.
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Affiliation(s)
- David Gnandt
- Institut für Physikalische Chemie, Universität Freiburg, Albertstraße 23a, 79104 Freiburg im Breisgau, Germany.
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6
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Muller MP, Jiang T, Sun C, Lihan M, Pant S, Mahinthichaichan P, Trifan A, Tajkhorshid E. Characterization of Lipid-Protein Interactions and Lipid-Mediated Modulation of Membrane Protein Function through Molecular Simulation. Chem Rev 2019; 119:6086-6161. [PMID: 30978005 PMCID: PMC6506392 DOI: 10.1021/acs.chemrev.8b00608] [Citation(s) in RCA: 153] [Impact Index Per Article: 30.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The cellular membrane constitutes one of the most fundamental compartments of a living cell, where key processes such as selective transport of material and exchange of information between the cell and its environment are mediated by proteins that are closely associated with the membrane. The heterogeneity of lipid composition of biological membranes and the effect of lipid molecules on the structure, dynamics, and function of membrane proteins are now widely recognized. Characterization of these functionally important lipid-protein interactions with experimental techniques is however still prohibitively challenging. Molecular dynamics (MD) simulations offer a powerful complementary approach with sufficient temporal and spatial resolutions to gain atomic-level structural information and energetics on lipid-protein interactions. In this review, we aim to provide a broad survey of MD simulations focusing on exploring lipid-protein interactions and characterizing lipid-modulated protein structure and dynamics that have been successful in providing novel insight into the mechanism of membrane protein function.
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Affiliation(s)
- Melanie P. Muller
- NIH Center for Macromolecular Modeling and Bioinformatics, Beckman Institute for Advanced Science and Technology
- Department of Biochemistry
- Center for Biophysics and Quantitative Biology
- College of Medicine
- University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Tao Jiang
- NIH Center for Macromolecular Modeling and Bioinformatics, Beckman Institute for Advanced Science and Technology
- Department of Biochemistry
- Center for Biophysics and Quantitative Biology
- University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Chang Sun
- NIH Center for Macromolecular Modeling and Bioinformatics, Beckman Institute for Advanced Science and Technology
- Department of Biochemistry
- University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Muyun Lihan
- NIH Center for Macromolecular Modeling and Bioinformatics, Beckman Institute for Advanced Science and Technology
- Department of Biochemistry
- Center for Biophysics and Quantitative Biology
- University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Shashank Pant
- NIH Center for Macromolecular Modeling and Bioinformatics, Beckman Institute for Advanced Science and Technology
- Department of Biochemistry
- Center for Biophysics and Quantitative Biology
- University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Paween Mahinthichaichan
- NIH Center for Macromolecular Modeling and Bioinformatics, Beckman Institute for Advanced Science and Technology
- Department of Biochemistry
- University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Anda Trifan
- NIH Center for Macromolecular Modeling and Bioinformatics, Beckman Institute for Advanced Science and Technology
- Department of Biochemistry
- Center for Biophysics and Quantitative Biology
- University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Emad Tajkhorshid
- NIH Center for Macromolecular Modeling and Bioinformatics, Beckman Institute for Advanced Science and Technology
- Department of Biochemistry
- Center for Biophysics and Quantitative Biology
- College of Medicine
- University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
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7
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Gahlawat G, Choudhury AR. A review on the biosynthesis of metal and metal salt nanoparticles by microbes. RSC Adv 2019; 9:12944-12967. [PMID: 35520790 PMCID: PMC9064032 DOI: 10.1039/c8ra10483b] [Citation(s) in RCA: 228] [Impact Index Per Article: 45.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Accepted: 04/17/2019] [Indexed: 12/11/2022] Open
Abstract
Metal nanoparticles have received great attention from researchers across the world because of a plethora of applications in agriculture and the biomedical field as antioxidants and antimicrobial compounds. Over the past few years, green nanotechnology has emerged as a significant approach for the synthesis and fabrication of metal nanoparticles. This green route employs various reducing and stabilizing agents from biological resources for the synthesis of nanoparticles. The present article aims to review the progress made in recent years on nanoparticle biosynthesis by microbes. These microbial resources include bacteria, fungi, yeast, algae and viruses. This review mainly focuses on the biosynthesis of the most commonly studied metal and metal salt nanoparticles such as silver, gold, platinum, palladium, copper, cadmium, titanium oxide, zinc oxide and cadmium sulphide. These nanoparticles can be used in pharmaceutical products as antimicrobial and anti-biofilm agents, targeted delivery of anticancer drugs, water electrolysis, waste water treatment, biosensors, biocatalysis, crop protection against pathogens, degradation of dyes etc. This review will discuss in detail various microbial modes of nanoparticles synthesis and the mechanism of their synthesis by various bioreducing agents such as enzymes, peptides, proteins, electron shuttle quinones and exopolysaccharides. A thorough understanding of the molecular mechanism of biosynthesis is the need of the hour to develop a technology for large scale production of bio-mediated nanoparticles. The present review also discusses the advantages of various microbial approaches in nanoparticles synthesis and lacuna involved in such processes. This review also highlights the recent milestones achieved on large scale production and future perspectives of nanoparticles.
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Affiliation(s)
- Geeta Gahlawat
- CSIR - Institute of Microbial Technology Sector 39A Chandigarh India +91 172 2695215 +91 172 6665312
| | - Anirban Roy Choudhury
- CSIR - Institute of Microbial Technology Sector 39A Chandigarh India +91 172 2695215 +91 172 6665312
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8
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Paquete CM, Rusconi G, Silva AV, Soares R, Louro RO. A brief survey of the "cytochromome". Adv Microb Physiol 2019; 75:69-135. [PMID: 31655743 DOI: 10.1016/bs.ampbs.2019.07.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Multihaem cytochromes c are widespread in nature where they perform numerous roles in diverse anaerobic metabolic pathways. This is achieved in two ways: multihaem cytochromes c display a remarkable diversity of ways to organize multiple hemes within the protein frame; and the hemes possess an intrinsic reactive versatility derived from diverse spin, redox and coordination states. Here we provide a brief survey of multihaem cytochromes c that have been characterized in the context of their metabolic role. The contribution of multihaem cytochromes c to dissimilatory pathways handling metallic minerals, nitrogen compounds, sulfur compounds, organic compounds and phototrophism are described. This aims to set the stage for the further exploration of the vast unknown "cytochromome" that can be anticipated from genomic databases.
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9
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Gnandt D, Na S, Koslowski T. Simulating biological charge transfer: Continuum dielectric theory or molecular dynamics? Biophys Chem 2018; 241:1-7. [PMID: 30036762 DOI: 10.1016/j.bpc.2018.07.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Accepted: 07/01/2018] [Indexed: 10/28/2022]
Abstract
We study the thermodynamic parameters of Marcus's theory of charge transfer, the driving forces and the reorganization energies, using two widely applied approaches to bioenergetic problems that seem to be radically different: continuum dielectric theory via a numerical solution of Poisson's equation, and the thermodynamic integration approach based upon classical Newtonian molecular dynamics, as perfomed by Na et al., PCCP 19, 18,938 (2017). With application to a nitrite reductase NrfHA protein heterodimer, we obtain an excellent agreement between the respective driving forces with an r.m.s. deviation of 1.7 kcal/mol, and a lower limit to the reorganization energies. The computational methods turn out to be mutually supportive: molecular dynamics can be used to determine the parameters of a dielectric theory computation, which on the other hand can be used to properly rescale the reorganization energies and partition them into aqueous and protein contributions. In addition, we use the electrostatic approach to study the influence of Ca2+ ions on the free energy landscape of charge transfer.
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Affiliation(s)
- David Gnandt
- Institut für Physikalische Chemie, Universität Freiburg, Albertstraße 23a, 79104 Freiburg im Breisgau, Germany
| | - Sehee Na
- Institut für Physikalische Chemie, Universität Freiburg, Albertstraße 23a, 79104 Freiburg im Breisgau, Germany
| | - Thorsten Koslowski
- Institut für Physikalische Chemie, Universität Freiburg, Albertstraße 23a, 79104 Freiburg im Breisgau, Germany.
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10
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Szamosvári D, Böttcher T. An Unsaturated Quinolone N-Oxide of Pseudomonas aeruginosa Modulates Growth and Virulence of Staphylococcus aureus. Angew Chem Int Ed Engl 2017; 56:7271-7275. [PMID: 28523838 DOI: 10.1002/anie.201702944] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Indexed: 01/15/2023]
Abstract
The pathogen Pseudomonas aeruginosa produces over 50 different quinolones, 16 of which belong to the class of 2-alkyl-4-quinolone N-oxides (AQNOs) with various chain lengths and degrees of saturation. We present the first synthesis of a previously proposed unsaturated compound that is confirmed to be present in culture extracts of P. aeruginosa, and its structure is shown to be trans-Δ1 -2-(non-1-enyl)-4-quinolone N-oxide. This compound is the most active agent against S. aureus, including MRSA strains, by more than one order of magnitude whereas its cis isomer is inactive. At lower concentrations, the compound induces small-colony variants of S. aureus, reduces the virulence by inhibiting hemolysis, and inhibits nitrate reductase activity under anaerobic conditions. These studies suggest that this unsaturated AQNO is one of the major agents that are used by P. aeruginosa to modulate competing bacterial species.
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Affiliation(s)
- Dávid Szamosvári
- Fachbereich Chemie, Konstanz Research School Chemical Biology, Zukunftskolleg, Universität Konstanz, 78457, Konstanz, Germany
| | - Thomas Böttcher
- Fachbereich Chemie, Konstanz Research School Chemical Biology, Zukunftskolleg, Universität Konstanz, 78457, Konstanz, Germany
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11
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Szamosvári D, Böttcher T. Ein ungesättigtes Chinolon-N-oxid vonPseudomonas aeruginosamoduliert Wachstum und Virulenz vonStaphylococcus aureus. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201702944] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Dávid Szamosvári
- Fachbereich Chemie, Konstanz Research School Chemical Biology, Zukunftskolleg; Universität Konstanz; 78457 Konstanz Deutschland
| | - Thomas Böttcher
- Fachbereich Chemie, Konstanz Research School Chemical Biology, Zukunftskolleg; Universität Konstanz; 78457 Konstanz Deutschland
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12
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Na S, Bauß A, Langenmaier M, Koslowski T. Thermodynamic integration network study of electron transfer: from proteins to aggregates. Phys Chem Chem Phys 2017; 19:18938-18947. [DOI: 10.1039/c7cp03030d] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We describe electron transfer through the NrfHA nitrite reductase using a thermodynamic integration scheme. Driving forces are hardly affected by dimerization, but the transport mechanism only emerges simulating the dimer.
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Affiliation(s)
- Sehee Na
- Institut für Physikalische Chemie
- Universität Freiburg
- D-79104 Freiburg im Breisgau
- Germany
| | - Anna Bauß
- Institut für Physikalische Chemie
- Universität Freiburg
- D-79104 Freiburg im Breisgau
- Germany
| | - Michael Langenmaier
- Institut für Physikalische Chemie
- Universität Freiburg
- D-79104 Freiburg im Breisgau
- Germany
| | - Thorsten Koslowski
- Institut für Physikalische Chemie
- Universität Freiburg
- D-79104 Freiburg im Breisgau
- Germany
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13
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Arshad A, Speth DR, de Graaf RM, Op den Camp HJM, Jetten MSM, Welte CU. A Metagenomics-Based Metabolic Model of Nitrate-Dependent Anaerobic Oxidation of Methane by Methanoperedens-Like Archaea. Front Microbiol 2015; 6:1423. [PMID: 26733968 PMCID: PMC4683180 DOI: 10.3389/fmicb.2015.01423] [Citation(s) in RCA: 120] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Accepted: 11/30/2015] [Indexed: 11/22/2022] Open
Abstract
Methane oxidation is an important process to mitigate the emission of the greenhouse gas methane and further exacerbating of climate forcing. Both aerobic and anaerobic microorganisms have been reported to catalyze methane oxidation with only a few possible electron acceptors. Recently, new microorganisms were identified that could couple the oxidation of methane to nitrate or nitrite reduction. Here we investigated such an enrichment culture at the (meta) genomic level to establish a metabolic model of nitrate-driven anaerobic oxidation of methane (nitrate-AOM). Nitrate-AOM is catalyzed by an archaeon closely related to (reverse) methanogens that belongs to the ANME-2d clade, tentatively named Methanoperedens nitroreducens. Methane may be activated by methyl-CoM reductase and subsequently undergo full oxidation to carbon dioxide via reverse methanogenesis. All enzymes of this pathway were present and expressed in the investigated culture. The genome of the archaeal enrichment culture encoded a variety of enzymes involved in an electron transport chain similar to those found in Methanosarcina species with additional features not previously found in methane-converting archaea. Nitrate reduction to nitrite seems to be located in the pseudoperiplasm and may be catalyzed by an unusual Nar-like protein complex. A small part of the resulting nitrite is reduced to ammonium which may be catalyzed by a Nrf-type nitrite reductase. One of the key questions is how electrons from cytoplasmically located reverse methanogenesis reach the nitrate reductase in the pseudoperiplasm. Electron transport in M. nitroreducens probably involves cofactor F420 in the cytoplasm, quinones in the cytoplasmic membrane and cytochrome c in the pseudoperiplasm. The membrane-bound electron transport chain includes F420H2 dehydrogenase and an unusual Rieske/cytochrome b complex. Based on genome and transcriptome studies a tentative model of how central energy metabolism of nitrate-AOM could work is presented and discussed.
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Affiliation(s)
- Arslan Arshad
- Department of Microbiology, Institute for Water and Wetland Research, Radboud University Nijmegen, Netherlands
| | - Daan R Speth
- Department of Microbiology, Institute for Water and Wetland Research, Radboud University Nijmegen, Netherlands
| | - Rob M de Graaf
- Department of Microbiology, Institute for Water and Wetland Research, Radboud University Nijmegen, Netherlands
| | - Huub J M Op den Camp
- Department of Microbiology, Institute for Water and Wetland Research, Radboud University Nijmegen, Netherlands
| | - Mike S M Jetten
- Department of Microbiology, Institute for Water and Wetland Research, Radboud University Nijmegen, Netherlands
| | - Cornelia U Welte
- Department of Microbiology, Institute for Water and Wetland Research, Radboud University Nijmegen, Netherlands
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14
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A Post-Genomic View of the Ecophysiology, Catabolism and Biotechnological Relevance of Sulphate-Reducing Prokaryotes. Adv Microb Physiol 2015. [PMID: 26210106 DOI: 10.1016/bs.ampbs.2015.05.002] [Citation(s) in RCA: 174] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Dissimilatory sulphate reduction is the unifying and defining trait of sulphate-reducing prokaryotes (SRP). In their predominant habitats, sulphate-rich marine sediments, SRP have long been recognized to be major players in the carbon and sulphur cycles. Other, more recently appreciated, ecophysiological roles include activity in the deep biosphere, symbiotic relations, syntrophic associations, human microbiome/health and long-distance electron transfer. SRP include a high diversity of organisms, with large nutritional versatility and broad metabolic capacities, including anaerobic degradation of aromatic compounds and hydrocarbons. Elucidation of novel catabolic capacities as well as progress in the understanding of metabolic and regulatory networks, energy metabolism, evolutionary processes and adaptation to changing environmental conditions has greatly benefited from genomics, functional OMICS approaches and advances in genetic accessibility and biochemical studies. Important biotechnological roles of SRP range from (i) wastewater and off gas treatment, (ii) bioremediation of metals and hydrocarbons and (iii) bioelectrochemistry, to undesired impacts such as (iv) souring in oil reservoirs and other environments, and (v) corrosion of iron and concrete. Here we review recent advances in our understanding of SRPs focusing mainly on works published after 2000. The wealth of publications in this period, covering many diverse areas, is a testimony to the large environmental, biogeochemical and technological relevance of these organisms and how much the field has progressed in these years, although many important questions and applications remain to be explored.
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15
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Korte HL, Saini A, Trotter VV, Butland GP, Arkin AP, Wall JD. Independence of nitrate and nitrite inhibition of Desulfovibrio vulgaris Hildenborough and use of nitrite as a substrate for growth. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:924-931. [PMID: 25534748 DOI: 10.1021/es504484m] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Sulfate-reducing microbes, such as Desulfovibrio vulgaris Hildenborough, cause “souring” of petroleum reservoirs through produced sulfide and precipitate heavy metals, either as sulfides or by alteration of the metal reduction state. Thus, inhibitors of these microbes, including nitrate and nitrite ions, are studied in order to limit their impact. Nitrite is a potent inhibitor of sulfate reducers, and it has been suggested that nitrate does not inhibit these microbes directly but by reduction to nitrite, which serves as the ultimate inhibitor. Here we provide evidence that nitrate inhibition of D. vulgaris can be independent of nitrite production. We also show that D. vulgaris can use nitrite as a nitrogen source or terminal electron acceptor for growth. Moreover, we report that use of nitrite as a terminal electron acceptor requires nitrite reductase (nrfA) as a D. vulgaris nrfA mutant cannot respire nitrite but remains capable of utilizing nitrite as a nitrogen source. These results illuminate previously uncharacterized metabolic abilities of D. vulgaris that may allow niche expansion in low-sulfate environments. Understanding these abilities may lead to better control of sulfate-reducing bacteria in industrial settings and more accurate prediction of their interactions in the environment.
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16
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Tikhonova TV, Popov VO. Structural and functional studies of multiheme cytochromes c involved in extracellular electron transport in bacterial dissimilatory metal reduction. BIOCHEMISTRY (MOSCOW) 2015; 79:1584-601. [DOI: 10.1134/s0006297914130094] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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17
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Abstract
Despite its reactivity and hence toxicity to living cells, sulfite is readily converted by various microorganisms using distinct assimilatory and dissimilatory metabolic routes. In respiratory pathways, sulfite either serves as a primary electron donor or terminal electron acceptor (yielding sulfate or sulfide, respectively), and its conversion drives electron transport chains that are coupled to chemiosmotic ATP synthesis. Notably, such processes are also seen to play a general role in sulfite detoxification, which is assumed to have an evolutionary ancient origin. The diversity of sulfite conversion is reflected by the fact that the range of microbial sulfite-converting enzymes displays different cofactors such as siroheme, heme c, or molybdopterin. This chapter aims to summarize the current knowledge of microbial sulfite metabolism and focuses on sulfite catabolism. The structure and function of sulfite-converting enzymes and the emerging picture of the modular architecture of the corresponding respiratory/detoxifying electron transport chains is emphasized.
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Affiliation(s)
- Jörg Simon
- Department of Biology, Microbial Energy Conversion and Biotechnology, Technische Universität Darmstadt, Schnittspahnstrasse 10, 64287 Darmstadt, Germany.
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18
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McMillan DGG, Marritt SJ, Firer-Sherwood MA, Shi L, Richardson DJ, Evans SD, Elliott SJ, Butt JN, Jeuken LJC. Protein-protein interaction regulates the direction of catalysis and electron transfer in a redox enzyme complex. J Am Chem Soc 2013; 135:10550-6. [PMID: 23799249 PMCID: PMC3823026 DOI: 10.1021/ja405072z] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
![]()
Protein–protein interactions
are well-known to regulate
enzyme activity in cell signaling and metabolism. Here, we show that
protein–protein interactions regulate the activity of a respiratory-chain
enzyme, CymA, by changing the direction or bias of catalysis. CymA,
a member of the widespread NapC/NirT superfamily, is a menaquinol-7
(MQ-7) dehydrogenase that donates electrons to several distinct terminal
reductases in the versatile respiratory network of Shewanella oneidensis. We report the incorporation
of CymA within solid-supported membranes that mimic the inner membrane
architecture of S. oneidensis. Quartz-crystal
microbalance with dissipation (QCM-D) resolved the formation of a
stable complex between CymA and one of its native redox partners,
flavocytochrome c3 (Fcc3) fumarate reductase.
Cyclic voltammetry revealed that CymA alone could only reduce MQ-7,
while the CymA-Fcc3 complex catalyzed the reaction required
to support anaerobic respiration, the oxidation of MQ-7. We propose
that MQ-7 oxidation in CymA is limited by electron transfer to the
hemes and that complex formation with Fcc3 facilitates
the electron-transfer rate along the heme redox chain. These results
reveal a yet unexplored mechanism by which bacteria can regulate multibranched
respiratory networks through protein–protein interactions.
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Affiliation(s)
- Duncan G G McMillan
- School of Biomedical Sciences, University of Leeds, Leeds LS2 9JT, United Kingdom
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19
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The prokaryotic Mo/W-bisPGD enzymes family: a catalytic workhorse in bioenergetic. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2013; 1827:1048-85. [PMID: 23376630 DOI: 10.1016/j.bbabio.2013.01.011] [Citation(s) in RCA: 103] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2012] [Revised: 01/21/2013] [Accepted: 01/23/2013] [Indexed: 01/05/2023]
Abstract
Over the past two decades, prominent importance of molybdenum-containing enzymes in prokaryotes has been put forward by studies originating from different fields. Proteomic or bioinformatic studies underpinned that the list of molybdenum-containing enzymes is far from being complete with to date, more than fifty different enzymes involved in the biogeochemical nitrogen, carbon and sulfur cycles. In particular, the vast majority of prokaryotic molybdenum-containing enzymes belong to the so-called dimethylsulfoxide reductase family. Despite its extraordinary diversity, this family is characterized by the presence of a Mo/W-bis(pyranopterin guanosine dinucleotide) cofactor at the active site. This review highlights what has been learned about the properties of the catalytic site, the modular variation of the structural organization of these enzymes, and their interplay with the isoprenoid quinones. In the last part, this review provides an integrated view of how these enzymes contribute to the bioenergetics of prokaryotes. This article is part of a Special Issue entitled: Metals in Bioenergetics and Biomimetics Systems.
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20
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Refojo PN, Ribeiro MA, Calisto F, Teixeira M, Pereira MM. Structural composition of alternative complex III: variations on the same theme. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2013; 1827:1378-82. [PMID: 23313414 DOI: 10.1016/j.bbabio.2013.01.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2012] [Revised: 12/21/2012] [Accepted: 01/02/2013] [Indexed: 01/10/2023]
Abstract
Alternative complex III forms a recently identified family of enzymes with quinol:electron acceptor oxidoreductase activity. First biochemical and genomic analyses showed that ACIII is composed of six to eight subunits, most of which homologous to different proteins or domains already observed in other known enzymatic complexes. The increasing number of completely sequenced genomes led us to perform a new search for the genes coding for the different ACIII subunits. We have identified a larger number of gene clusters coding for ACIII, still confined to the bacterial domain, but extended to classes in which it was not observed before. We also found an unanticipated diversity in gene clusters, both in terms of its constitution and organization. The several unexpected gene arrangements brought new perspectives to the role of the different subunits of ACIII, namely in quinone binding and in proton translocation. This article is part of a Special Issue entitled: Respiratory complex III and related bc complexes.
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Affiliation(s)
- Patrícia N Refojo
- Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Av. da República EAN, 2780-157 Oeiras, Portugal
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21
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The quest to achieve the detailed structural and functional characterization of CymA. Biochem Soc Trans 2012; 40:1291-4. [PMID: 23176470 DOI: 10.1042/bst20120114] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Shewanella oneidensis MR-1 is a sediment organism capable of dissimilatory reduction of insoluble metal compounds such as those of Fe(II) and Mn(IV). This bacterium has been used as a model organism for potential applications in bioremediation of contaminated environments and in the production of energy in microbial fuel cells. The capacity of Shewanella to perform extracellular reduction of metals is linked to the action of several multihaem cytochromes that may be periplasmic or can be associated with the inner or outer membrane. One of these cytochromes is CymA, a membrane-bound tetrahaem cytochrome localized in the periplasm that mediates the electron transfer between the quinone pool in the cytoplasmic membrane and several periplasmic proteins. Although CymA has the capacity to regulate multiple anaerobic respiratory pathways, little is known about the structure and functional mechanisms of this focal protein. Understanding the structure and function of membrane proteins is hampered by inherent difficulties associated with their purification since the choice of the detergents play a critical role in the protein structure and stability. In the present mini-review, we detail the current state of the art in the characterization of CymA, and add recent information on haem structural behaviour for CymA solubilized in different detergents. These structural differences are deduced from NMR spectroscopy data that provide information on the geometry of the haem axial ligands. At least two different conformational forms of CymA are observed for different detergents, which seem to be related to the micelle size. These results provide guidance for the discovery of the most promising detergent that mimics the native lipid bilayer and is compatible with biochemical and structural studies.
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22
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Dikanov SA. Resolving protein-semiquinone interactions by two-dimensional ESEEM spectroscopy. ELECTRON PARAMAGNETIC RESONANCE 2012. [DOI: 10.1039/9781849734837-00103] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- S. A. Dikanov
- University of Illinois at Urbana-Champaign, Department of Veterinary Clinical Medicine 190 MSB, 506 S. Mathews Ave., Urbana IL 61801 USA
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23
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Heylen K, Keltjens J. Redundancy and modularity in membrane-associated dissimilatory nitrate reduction in Bacillus. Front Microbiol 2012; 3:371. [PMID: 23087684 PMCID: PMC3475470 DOI: 10.3389/fmicb.2012.00371] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2012] [Accepted: 09/28/2012] [Indexed: 11/13/2022] Open
Abstract
The genomes of two phenotypically denitrifying type strains of the genus Bacillus were sequenced and the pathways for dissimilatory nitrate reduction were reconstructed. Results suggest that denitrification proceeds in the periplasmic space and in an analogous fashion as in Gram-negative organisms, yet with the participation of proteins that tend to be membrane-bound or membrane-associated. A considerable degree of functional redundancy was observed with marked differences between B. azotoformans LMG 9581(T) and B. bataviensis LMG 21833(T). In addition to the already characterized menaquinol/cyt c-dependent nitric oxide reductase (Suharti et al., 2001, 2004) of which the encoding genes could be identified now, evidence for another novel nitric oxide reductase (NOR) was found. Also, our analyses confirm earlier findings on branched electron transfer with both menaquinol and cytochrome c as reductants. Quite unexpectedly, both bacilli have the disposal of two parallel pathways for nitrite reduction enabling a life style as a denitrifier and as an ammonifying bacterium.
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Affiliation(s)
- Kim Heylen
- Laboratory of Microbiology, Department of Biochemistry and Microbiology, University of Ghent Gent, Belgium
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24
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Tikhonova T, Tikhonov A, Trofimov A, Polyakov K, Boyko K, Cherkashin E, Rakitina T, Sorokin D, Popov V. Comparative structural and functional analysis of two octaheme nitrite reductases from closely relatedThioalkalivibriospecies. FEBS J 2012; 279:4052-61. [DOI: 10.1111/j.1742-4658.2012.08811.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Tamara Tikhonova
- Bach Institute of Biochemistry; Russian Academy of Sciences, Leninskii pr. 33; Moscow 119071; Russia
| | - Alexey Tikhonov
- Bach Institute of Biochemistry; Russian Academy of Sciences, Leninskii pr. 33; Moscow 119071; Russia
| | | | | | | | - Eugene Cherkashin
- National Research Centre ‘Kurchatov Institute’, Academic Kurchatov sq. 1; Moscow 123182; Russia
| | - Tatiana Rakitina
- National Research Centre ‘Kurchatov Institute’, Academic Kurchatov sq. 1; Moscow 123182; Russia
| | - Dmitry Sorokin
- Winogradsky Institute of Microbiology; Russian Academy of Sciences, Leninskii pr. 32a; Moscow 119991; Russia
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25
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Simon J, Klotz MG. Diversity and evolution of bioenergetic systems involved in microbial nitrogen compound transformations. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2012; 1827:114-35. [PMID: 22842521 DOI: 10.1016/j.bbabio.2012.07.005] [Citation(s) in RCA: 214] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2012] [Revised: 07/10/2012] [Accepted: 07/19/2012] [Indexed: 11/18/2022]
Abstract
Nitrogen is an essential element of life that needs to be assimilated in its most reduced form, ammonium. On the other hand, nitrogen exists in a multitude of oxidation states and, consequently, nitrogen compounds (NCs) serve as electron donor and/or acceptors in many catabolic pathways including various forms of microbial respiration that contribute to the global biogeochemical nitrogen cycle. Some of these NCs are also known as reactive nitrogen species able to cause nitrosative stress because of their high redox reactivity. The best understood processes of the nitrogen cycle are denitrification and ammonification (both beginning with nitrate reduction to nitrite), nitrification (aerobic oxidation of ammonium and nitrite) and anaerobic ammonium oxidation (anammox). This review presents examples of the diverse architecture, either elucidated or anticipated, and the high degree of modularity of the corresponding respiratory electron transport processes found in Bacteria and Archaea, and relates these to their respective bioenergetic mechanisms of proton motive force generation. In contrast to the multiplicity of enzymes that catalyze NC transformations, the number of proteins or protein modules involved in connecting electron transport to and from these enzymes with the quinone/quinol pool is comparatively small. These quinone/quinol-reactive protein modules consist of cytochromes b and c and iron-sulfur proteins. Conclusions are drawn towards the evolutionary relationships of bioenergetic systems involved in NC transformation and deduced aspects of the evolution of the biogeochemical nitrogen cycle are presented. This article is part of a Special Issue entitled: The evolutionary aspects of bioenergetic systems.
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Affiliation(s)
- Jörg Simon
- Microbial Energy Conversion and Biotechnology, Department of Biology, Technische Universität Darmstadt, Schnittspahnstr. 10, 64287 Darmstadt, Germany.
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26
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Marritt SJ, Lowe TG, Bye J, McMillan DGG, Shi L, Fredrickson J, Zachara J, Richardson DJ, Cheesman MR, Jeuken LJC, Butt JN. A functional description of CymA, an electron-transfer hub supporting anaerobic respiratory flexibility in Shewanella. Biochem J 2012; 444:465-74. [PMID: 22458729 DOI: 10.1042/bj20120197] [Citation(s) in RCA: 90] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2023]
Abstract
CymA (tetrahaem cytochrome c) is a member of the NapC/NirT family of quinol dehydrogenases. Essential for the anaerobic respiratory flexibility of shewanellae, CymA transfers electrons from menaquinol to various dedicated systems for the reduction of terminal electron acceptors including fumarate and insoluble minerals of Fe(III). Spectroscopic characterization of CymA from Shewanella oneidensis strain MR-1 identifies three low-spin His/His co-ordinated c-haems and a single high-spin c-haem with His/H(2)O co-ordination lying adjacent to the quinol-binding site. At pH 7, binding of the menaquinol analogue, 2-heptyl-4-hydroxyquinoline-N-oxide, does not alter the mid-point potentials of the high-spin (approximately -240 mV) and low-spin (approximately -110, -190 and -265 mV) haems that appear biased to transfer electrons from the high- to low-spin centres following quinol oxidation. CymA is reduced with menadiol (E(m) = -80 mV) in the presence of NADH (E(m) = -320 mV) and an NADH-menadione (2-methyl-1,4-naphthoquinone) oxidoreductase, but not by menadiol alone. In cytoplasmic membranes reduction of CymA may then require the thermodynamic driving force from NADH, formate or H2 oxidation as the redox poise of the menaquinol pool in isolation is insufficient. Spectroscopic studies suggest that CymA requires a non-haem co-factor for quinol oxidation and that the reduced enzyme forms a 1:1 complex with its redox partner Fcc3 (flavocytochrome c3 fumarate reductase). The implications for CymA supporting the respiratory flexibility of shewanellae are discussed.
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Affiliation(s)
- Sophie J Marritt
- Centre for Molecular and Structural Biochemistry, School of Chemistry and School of Biological Sciences, University of East Anglia, Norwich NR4 7TJ, U.K
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27
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Todorovic S, Rodrigues ML, Matos D, Pereira IAC. Redox properties of lysine- and methionine-coordinated hemes ensure downhill electron transfer in NrfH2A4 nitrite reductase. J Phys Chem B 2012; 116:5637-43. [PMID: 22519292 DOI: 10.1021/jp301356m] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The multiheme NrfHA nitrite reductase is a menaquinol:nitrite oxidoreductase that catalyzes the 6-electron reduction of nitrite to ammonia in a reaction that involves eight protons. X-ray crystallography of the enzyme from Desulfovibrio vulgaris revealed that the biological unit, NrfH2A4, houses 28 c-type heme groups, 22 of them with low spin and 6 with pentacoordinated high spin configuration. The high spin hemes, which are the electron entry and exit points of the complex, carry a highly unusual coordination for c-type hemes, lysine and methionine as proximal ligands in NrfA and NrfH, respectively. Employing redox titrations followed by X-band EPR spectroscopy and surface-enhanced resonance Raman spectroelectrochemistry, we provide the first experimental evidence for the midpoint redox potential of the NrfH menaquinol-interacting methionine-coordinated heme (-270 ± 10 mV, z = 0.96), identified by the use of the inhibitor HQNO, a structural analogue of the physiological electron donor. The redox potential of the catalytic lysine-coordinated high spin heme of NrfA is -50 ± 10 mV, z = 0.9. These values determined for the integral NrfH2A4 complex indicate that a driving force for a downhill electron transfer is ensured in this complex.
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Affiliation(s)
- Smilja Todorovic
- Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa , Av. da Republica, 2780-157 Oeiras, Portugal
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28
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McMillan DGG, Marritt SJ, Butt JN, Jeuken LJC. Menaquinone-7 is specific cofactor in tetraheme quinol dehydrogenase CymA. J Biol Chem 2012; 287:14215-25. [PMID: 22393052 PMCID: PMC3340143 DOI: 10.1074/jbc.m112.348813] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Little is known about enzymatic quinone-quinol interconversions in the lipid membrane when compared with our knowledge of substrate transformations by globular enzymes. Here, the smallest example of a quinol dehydrogenase in nature, CymA, has been studied. CymA is a monotopic membrane tetraheme c-type cytochrome belonging to the NapC/NirT family and central to anaerobic respiration in Shewanella sp. Using protein-film electrochemistry, it is shown that vesicle-bound menaquinone-7 is not only a substrate for this enzyme but is also required as a cofactor when converting other quinones. Here, we propose that the high concentration of quinones in the membrane negates the evolutionary pressure to create a high affinity active site. However, the instability and reactivity of reaction intermediate, semiquinone, might require a cofactor that functions to minimize damaging side reactions.
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Affiliation(s)
- Duncan G G McMillan
- Institute of Membrane and Systems Biology, University of Leeds, Leeds LS2 9JT, United Kingdom
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29
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Shi L, Rosso KM, Clarke TA, Richardson DJ, Zachara JM, Fredrickson JK. Molecular Underpinnings of Fe(III) Oxide Reduction by Shewanella Oneidensis MR-1. Front Microbiol 2012; 3:50. [PMID: 22363328 PMCID: PMC3279761 DOI: 10.3389/fmicb.2012.00050] [Citation(s) in RCA: 125] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2011] [Accepted: 01/30/2012] [Indexed: 11/25/2022] Open
Abstract
In the absence of O2 and other electron acceptors, the Gram-negative bacterium Shewanella oneidensis MR-1 can use ferric [Fe(III)] (oxy)(hydr)oxide minerals as the terminal electron acceptors for anaerobic respiration. At circumneutral pH and in the absence of strong complexing ligands, Fe(III) oxides are relatively insoluble and thus are external to the bacterial cells. S. oneidensis MR-1 and related strains of metal-reducing Shewanella have evolved machinery (i.e., metal-reducing or Mtr pathway) for transferring electrons from the inner-membrane, through the periplasm and across the outer-membrane to the surface of extracellular Fe(III) oxides. The protein components identified to date for the Mtr pathway include CymA, MtrA, MtrB, MtrC, and OmcA. CymA is an inner-membrane tetraheme c-type cytochrome (c-Cyt) that belongs to the NapC/NrfH family of quinol dehydrogenases. It is proposed that CymA oxidizes the quinol in the inner-membrane and transfers the released electrons to MtrA either directly or indirectly through other periplasmic proteins. A decaheme c-Cyt, MtrA is thought to be embedded in the trans outer-membrane and porin-like protein MtrB. Together, MtrAB deliver the electrons through the outer-membrane to the MtrC and OmcA on the outmost bacterial surface. MtrC and OmcA are the outer-membrane decaheme c-Cyts that are translocated across the outer-membrane by the bacterial type II secretion system. Functioning as terminal reductases, MtrC and OmcA can bind the surface of Fe(III) oxides and transfer electrons directly to these minerals via their solvent-exposed hemes. To increase their reaction rates, MtrC and OmcA can use the flavins secreted by S. oneidensis MR-1 cells as diffusible co-factors for reduction of Fe(III) oxides. Because of their extracellular location and broad redox potentials, MtrC and OmcA can also serve as the terminal reductases for soluble forms of Fe(III). In addition to Fe(III) oxides, Mtr pathway is also involved in reduction of manganese oxides and other metals. Although our understanding of the Mtr pathway is still far from complete, it is the best characterized microbial pathway used for extracellular electron exchange. Characterizations of the Mtr pathway have made significant contributions to the molecular understanding of microbial reduction of Fe(III) oxides.
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Affiliation(s)
- Liang Shi
- Pacific Northwest National Laboratory Richland, WA, USA
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30
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Matsumoto Y, Tosha T, Pisliakov AV, Hino T, Sugimoto H, Nagano S, Sugita Y, Shiro Y. Crystal structure of quinol-dependent nitric oxide reductase from Geobacillus stearothermophilus. Nat Struct Mol Biol 2012; 19:238-45. [PMID: 22266822 DOI: 10.1038/nsmb.2213] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2011] [Accepted: 11/22/2011] [Indexed: 11/09/2022]
Abstract
The structure of quinol-dependent nitric oxide reductase (qNOR) from G. stearothermophilus, which catalyzes the reduction of NO to produce the major ozone-depleting gas N(2)O, has been characterized at 2.5 Å resolution. The overall fold of qNOR is similar to that of cytochrome c-dependent NOR (cNOR), and some structural features that are characteristic of cNOR, such as the calcium binding site and hydrophilic cytochrome c domain, are observed in qNOR, even though it harbors no heme c. In contrast to cNOR, structure-based mutagenesis and molecular dynamics simulation studies of qNOR suggest that a water channel from the cytoplasm can serve as a proton transfer pathway for the catalytic reaction. Further structural comparison of qNOR with cNOR and aerobic and microaerobic respiratory oxidases elucidates their evolutionary relationship and possible functional conversions.
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Affiliation(s)
- Yushi Matsumoto
- Biometal Science Laboratory, RIKEN SPring-8 Center, Sayo, Hyogo, Japan
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31
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Einsle O. Structure and Function of Formate-Dependent Cytochrome c Nitrite Reductase, NrfA. Methods Enzymol 2011; 496:399-422. [DOI: 10.1016/b978-0-12-386489-5.00016-6] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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32
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Zargar K, Saltikov CW. Lysine-91 of the tetraheme c-type cytochrome CymA is essential for quinone interaction and arsenate respiration in Shewanella sp. strain ANA-3. Arch Microbiol 2009; 191:797-806. [PMID: 19760266 PMCID: PMC2762525 DOI: 10.1007/s00203-009-0511-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2009] [Revised: 08/24/2009] [Accepted: 09/02/2009] [Indexed: 11/08/2022]
Abstract
The tetraheme c-type cytochrome, CymA, is essential for arsenate respiratory reduction in Shewanella sp. ANA-3, a model arsenate reducer. CymA is predicted to mediate electron transfer from quinols to the arsenate respiratory reductase (ArrAB). Here, we present biochemical and physiological evidence that CymA interacts with menaquinol (MQH2) substrates. Fluorescence quench titration with the MQH2 analog, 2-n-heptyl-4-hydroxyquinoline-N-oxide (HOQNO), was used to demonstrate quinol binding of E. coli cytoplasmic membranes enriched with various forms of CymA. Wild-type CymA bound HOQNO with a Kd of 0.1–1 μM. It was also shown that the redox active MQH2 analog, 2,3-dimethoxy-1,4-naphthoquinone (DMNH2), could reduce CymA in cytoplasmic membrane preparations. Based on a CymA homology model made from the NrfH tetraheme cytochrome structure, it was predicted that Lys91 would be involved in CymA-quinol interactions. CymA with a K91Q substitution showed little interaction with HOQNO. In addition, DMNH2-dependent reduction of CymA-K91Q was diminished by 45% compared to wild-type CymA. A ΔcymA ANA-3 strain containing a plasmid copy of cymA-K91Q failed to grow with arsenate as an electron acceptor. These results suggest that Lys91 is physiologically important for arsenate respiration and support the hypothesis that CymA interacts with menaquinol resulting in the reduction of the cytochrome.
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Affiliation(s)
- Kamrun Zargar
- Department of Microbiology and Environmental Toxicology, University of California, 1156 High Street, Santa Cruz, CA 95064, USA
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33
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Kern M, Simon J. Electron transport chains and bioenergetics of respiratory nitrogen metabolism in Wolinella succinogenes and other Epsilonproteobacteria. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2009; 1787:646-56. [PMID: 19171117 DOI: 10.1016/j.bbabio.2008.12.010] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2008] [Accepted: 12/23/2008] [Indexed: 12/16/2022]
Abstract
Recent phylogenetic analyses have established that the Epsilonproteobacteria form a globally ubiquitous group of ecologically significant organisms that comprises a diverse range of free-living bacteria as well as host-associated organisms like Wolinella succinogenes and pathogenic Campylobacter and Helicobacter species. Many Epsilonproteobacteria reduce nitrate and nitrite and perform either respiratory nitrate ammonification or denitrification. The inventory of epsilonproteobacterial genomes from 21 different species was analysed with respect to key enzymes involved in respiratory nitrogen metabolism. Most ammonifying Epsilonproteobacteria employ two enzymic electron transport systems named Nap (periplasmic nitrate reductase) and Nrf (periplasmic cytochrome c nitrite reductase). The current knowledge on the architecture and function of the corresponding proton motive force-generating respiratory chains using low-potential electron donors are reviewed in this article and the role of membrane-bound quinone/quinol-reactive proteins (NapH and NrfH) that are representative of widespread bacterial electron transport modules is highlighted. Notably, all Epsilonproteobacteria lack a napC gene in their nap gene clusters. Possible roles of the Nap and Nrf systems in anabolism and nitrosative stress defence are also discussed. Free-living denitrifying Epsilonproteobacteria lack the Nrf system but encode cytochrome cd(1) nitrite reductase, at least one nitric oxide reductase and a characteristic cytochrome c nitrous oxide reductase system (cNosZ). Interestingly, cNosZ is also found in some ammonifying Epsilonproteobacteria and enables nitrous oxide respiration in W. succinogenes.
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Affiliation(s)
- Melanie Kern
- Institute of Molecular Biosciences, Goethe University, Max-von-Laue-Str. 9, 60438 Frankfurt am Main, Germany
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Quinone-reactive proteins devoid of haem b form widespread membrane-bound electron transport modules in bacterial respiration. Biochem Soc Trans 2008; 36:1011-6. [DOI: 10.1042/bst0361011] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Many quinone-reactive enzyme complexes that are part of membrane-integral eukaryotic or prokaryotic respiratory electron transport chains contain one or more haem b molecules embedded in the membrane. In recent years, various novel proteins have emerged that are devoid of haem b but are thought to fulfil a similar function in bacterial anaerobic respiratory systems. These proteins are encoded by genes organized in various genomic arrangements and are thought to form widespread membrane-bound quinone-reactive electron transport modules that exchange electrons with redox partner proteins located at the outer side of the cytoplasmic membrane. Prototypic representatives are the multihaem c-type cytochromes NapC, NrfH and TorC (NapC/NrfH family), the putative iron–sulfur protein NapH and representatives of the NrfD/PsrC family. Members of these protein families vary in the number of their predicted transmembrane segments and, consequently, diverse quinone-binding sites are expected. Only a few of these enzymes have been isolated and characterized biochemically and high-resolution structures are limited. This mini-review briefly summarizes predicted and experimentally demonstrated properties of the proteins in question and discusses their role in electron transport and bioenergetics of anaerobic respiration.
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